Japanese markets tumbled as tech stocks succumbed to profit taking and a survey showed Japan's manufacturing activity shrank at the fastest pace in 19 months in October.
The Nikkei average fell 1.74 percent to 51,497.20 as traders returned to their desks after a long holiday weekend. The broader Topix index closed 0.65 percent lower at 3,310.14.
Technology investor SoftBank Group plunged 7 percent and chip-testing equipment maker Advantest plummeted 5.9 percent.